Consider again the two-way ANOVA hypothesis test described in Problem 28.

a. Advertising agency 1 claims that the mean increase in ticket sales per advertising dollar Owing to its Web site-based advertisements is greater than the average increase in sales arising from other types of ads prepared by its firm. Is this claim supported by the given data? Explain.

b. Advertising agency 2 claims that the mean increase in ticket sales per advertising dollar Owing to its Web site-based advertisements is greater than the average increase in sales arising from other ads prepared by its firm or the competition. Is this claim supported by the given data? Explain.

Problem 28

A commuter airline wants to determine the combination of advertising medium (four levels) and advertising agency (two levels) that would produce the largest increase in ticket sales per advertising dollar spent. Each of the two advertising agencies has prepared advertisements in formats required for distribution by each of the media (including television, radio, newspaper, and Web site). Forty small towns of roughly the same size have been selected for this experiment. Furthermore, groups of five of these small towns have been assigned to receive an advertisement prepared and distributed by each of the eight agency—medium combinations. The dollar increases in ticket sales per advertising dollar spent, based on a 1-month period, are given in the file P12_28.XLS. Test for any significant main effects and interactions at the 5% level, and briefly summarize your results.